1. Field of the Invention
The present invention relates to the field of remote distribution of video imagery over a computer communications network.
2. Description of the Related Art
The conventional video display for a computing device has been widely used for many years. The primary function of the video display includes providing a medium for rendering a user interface through which an end-user can interact with an underlying application in the computing device, and for presenting audiovisual content. For most fixed computing devices, including personal computers, there is little practical limit of the resolution and size of an image that can be displayed in the display. The same is not true of other computing devices. In fact, for the typical pervasive device, display space comes at a premium.
“Pervasive computing” refers to any non-constrained computing device not physically tethered to a data communications network. Thus, pervasive computing devices refer not only to computers wirelessly linked to networks, but also to handheld computing devices, cellular telephones, wearable systems, embedded computing systems and the like. In the case of pervasive devices, the display area sometimes can be limited to as little as a 160 pixel by 160 pixel region or less. Thus, for conventional Web browsing, the display area of the typical pervasive device can be quite limiting.
Despite the inherent size limitations of its display, the pervasive device not only can be used to view the static content of the ordinary Web page, but also audiovisual material provided by an audiovisual source over a computer communications network such as the global Internet. To facilitate the transmission of video imagery over the Internet to a pervasive device, oftentimes the video imagery can be compressed. One popular form of compression includes “run length encoding”. Run length encoding is a simple form of data compression in which identical data values within a sequence of data are stored as a single value with an indication of “count” as it is well known in the art. Run length encoding, like other compression schemes, can be taxing on computing resources.
Generally, resource consumption is a necessary consequence of video compression, however on occasion resources are needlessly consumed during video compression. In illustration, FIG. 3 is a flow chart depicting a process for image scaling for screen size known in the art. As shown in FIG. 3, two different video images 330A, 330B can be compared and a differential image 350 can be computed through an exclusive or operation 340. The differential image 350 can be compressed in block 360 and only then, can the compressed image be scaled in block 370 to produce a compress, scaled form of the image 380 suitable for transmission to a target device. Thus, it will be apparent that computing resources will have been squandered on aspects of the differential image 350 that will not survive scaling in block 370.
For the individual circumstance where a single file is to be compressed at a time, the resulting resource consumption can be of no consequence. However, in an environment where video is to be distributed to a vast number of pervasive devices disposed about a wide scale computer communications network such as the Internet, the repeated and frequent compression of the video can place an undesirable burden on the computing resources of the video server. To compound matters, once the pervasive device has received compressed imagery, the pervasive device must resize the decompressed imagery to meet the display size limitations of the pervasive device undesirably consuming yet additional process resources.